Film dressings are transparent, flexible and adhesive, and are used for superficial wounds or those expected to heal without complication. They are designed to protect the wound from friction and damage and also provide a barrier against microorganisms. They can also be used for fixation/around stoma sites, etc. Most film dressings allow the healthcare professional to visualise the wound and its progress without being removed.
Film dressings should not be used for deeper (full-thickness) wounds, wounds that are infected, or those that are producing moderate-to-large amounts of wound fluid (exudate). Some films have an absorbent pad, which has some absorbency, but also means that they are not transparent. There are also others available that have a waterproof backing, which can protect the wound from water when bathing/showering and contamination.
How do film dressings work?
Film dressings are usually made from a thin polyurethane membrane, which is coated with adhesive. However, in patients with fragile skin, atraumatic versions can be used. Their main role is to protect the wound and they are unable to absorb large amounts of exudate (Fletcher, 2012), although, as mentioned above, some versions do have an adhesive pad that can absorb some moisture.
Film dressings act as a ‘second skin’ — some are occlusive (in that they are air- and water-tight), while others are moisture- and oxygen-permeable to varying degrees. This moisture vapour permeability allows excess moisture to evaporate through the dressing, while maintaining a moist wound environment conducive to healing (Jones et al, 2006). The rate at which the dressing allows moisture to evaporate is known as the moisture vapour transmission rate (MVTR). Different film dressings will have a low, medium or high MVTR, the latter resulting in quick moisture loss. It is important to check the specifications of the dressing and match the appropriate dressing to the conditions of the wound, e.g. wounds with medium volumes of exudate may require a dressing with a high MVTR or film with a pad; a wound that needs observation would need transparent film.
Remember that these dressings cannot deal with high volumes of exudate.
What kind of wounds should a film dressing be used on?
Film dressings are mainly used for shallow and/or simple wounds such as cuts, abrasions and scalding. They can also be used on burns and to cover sutures and catheter sites.
There are a number of film products available — how can I choose the correct one?
Each patient will have different wound care needs that need to be considered when choosing the right product. The following questions will help with dressing selection.
Does the wound need debriding?
Film dressings can help to facilitate a form of debridement known as autolytic debridement. This is where the body’s own moisture and enzymatic activity are used to hydrate, soften and eventually remove dead tissue (necrosis). This occurs by using a dressing that keeps the wound fluid in contact with the necrotic tissue. Autolytic debridement is useful in that it not only removes necrotic tissue, but is also painless.
Can film dressings help to fight infection?
Although film dressings can provide a barrier against infection as they help to keep microorganisms out of a wound, they should not be applied to wounds that are already infected, as these can produce large volumes of exudate.
What is an absorbent film dressing?
There are film dressings available that can absorb larger amounts of exudate. These are known as absorbent or ‘island’ dressings, as they feature an absorbent central pad, which is surrounded by film (Sussman, 2012). These are able to absorb greater volumes of exudate than a ‘normal’ film, although caution should still be exercised in highly exuding wounds.
Other films incorporate foam, an acrylic absorbent pad or have a higher MVTR than conventional film dressings, again helping them to process moisture.
Note: the use of a film dressing should always be re-evaluated if exudate volumes begin to rise. If in doubt, consult local policies.
Other types of film dressings
Some film dressings come with in-built properties that help the wound to heal. For example, film dressings are available that contain iodine (for its antimicrobial properties), whereas others are designed to cover catheter sites.
Points to remember when applying a film dressing
As film dressings are not able to absorb large amounts of moisture, maceration of the surrounding skin can be a problem if the wound is producing too much fluid that cannot escape. Healthcare professionals should be aware of ‘pooling’, where the wound begins to produce more fluid than the dressing can cope with (Sussman, 2012).
It is also important to ensure that the film adequately covers the wound, leaving a small margin, and that the surrounding skin is not wet, oily or ‘greasy’ from creams or ointments.
One advantage of film dressings is that they can be worn in the shower due to their waterproof properties. They are also often used as a secondary dressing to keep other dressings in place (Fletcher, 2012), as well as protecting wounds from contamination in vulnerable areas, such as the sacrum.
Removal of a film dressing
Due to their adherent component, it is vital that film dressings are not pulled hard or ‘tugged’, as this may damage delicate underlying skin and cause further pain and trauma.
Caution should be used when considering the use of adherent film dressings in skin tears, where the act of removal can damage the fragile skin further.
Although cost-effectiveness is important, choosing the cheapest film dressing is not necessarily the best thing to do, as dressing choice should always be guided by the patient’s needs. If a dressing fails to perform well, more frequent dressing changes will be needed, incurring greater nursing time.
Patient choice and preference should always be considered. This helps to build up a good nursing–patient relationship and is in line with national policy.
- Antimicrobial properties